Rpo G86 locking differential

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GMFORLIFE

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My truck has the G86 option.
RPO G86 Limited slip differs from the RPO G80 in what fashion?
What's the chances the clutch packs are still functioning?
Thanks.
 

hatzie

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Picture of the SPID?
 

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@89Suburban 's Burb had a G80 code and he had a LSD in his instead of the Gov-Bomb. I think we determined it was an Auburn LSD unit and I believe he said it worked fine.
 

89Suburban

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@89Suburban 's Burb had a G80 code and he had a LSD in his instead of the Gov-Bomb. I think we determined it was an Auburn LSD unit and I believe he said it worked fine.
In both the '89 and the '90.
 

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He's got some interesting RPO codes on that sticker. Like how rare is it to see M49 (If that's an M, sunglight jacked the pic) I see lots of MX0 and MX1 but I don't recall seeing M49. I'm sure I have, but it couldn't have been many.
 

RetroC10Sport

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He's got some interesting RPO codes on that sticker. Like how rare is it to see M49 (If that's an M, sunglight jacked the pic) I see lots of MX0 and MX1 but I don't recall seeing M49. I'm sure I have, but it couldn't have been many.

M49 means Turbo Hydramatic like all of them got (although I once came across a C30 CC where someone installed a powerglide.) if the automatic is specified. My daughter's truck has M49 too.
 

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G80 was the Eaton gov lock

G86 was limited slip on automobile chassis like the F-Bodies. Prolly the same on the light trucks.

G87 ?

I need to look at the 85-91 parts books...
 

RetroC10Sport

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G80 was the Eaton gov lock

G86 was limited slip on automobile chassis like the F-Bodies. Prolly the same on the light trucks.

G87 ?

I need to look at the 85-91 parts books...

Or see post above. :waytogo:This is on a '73.
 

hatzie

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That's a rather strange SPID...:confused:

Production Options in the 1973-1978 GM Light Truck 51a parts books don't list G86 at all. The references I do find for G86 Limited slip is in the GM automobile parts books.

I'm not finding G87 in the 73-78 light truck parts books either.
79-84 parts book 52a shows G87 = Gear, Ring, 8.50 IN

G80 = AXLE - REAR LOCKING TYPE... from 73-93

Now that I've seen the SPID with an RPO that shouldn't be there... I'd be interested to know what the code stamped into the axle tube is.

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bucket

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In both the '89 and the '90.

And I still think that's crazy odd. I wonder if it was due to a shortage, and Caprice units were installed

1973 axle:
G80 - positraction
G86 - Eaton locking diff
G87 - maximum traction (C30 camper special with dual rear wheels only)

So there WAS at some point a locking diff available for a dually D70?
 

RetroC10Sport

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That's a rather strange SPID...

Production Options in the 1973-1978 GM Light Truck 51a parts books don't list G86 at all. The references I do find for G86 Limited slip is in the GM automobile parts books.

I'm not finding G87 in the 73-78 light truck parts books either.
79-84 parts book 52a shows G87 = Gear, Ring, 8.50 IN

G80 = AXLE - REAR LOCKING TYPE... from 73-93

I'd be interested to know what the code stamped into the axle tube is.

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